But you might not know about the Florida company whose products Oz pushed and the company's history of questionable business dealings. Nicholas Congleton, Bryan Walsh, and Paul Pascual were sued last month by the Federal Trade Commission for selling a product called Green Coffee Extract.

It's not the first time that one member of the trio, Congleton, has been sued for duping customers.

After Dr. Oz gave Green Coffee Extract backing on his show -- including telling viewers they could drop 20 pounds in four weeks, calling it "the magic weight loss cure for every body type'' -- the product was sold on various websites at $50 for a month's supply.

The FTC alleges in its suit that Congleton, Walsh, and Pascual sold the weight loss supplement through companies under the names of NPB Advertising Inc., Nationwide Ventures LLC, Olympus Advertising Inc., JMD Advertising Inc., and Signature Group LLC.

The trio, who hail from the Tampa area, didn't tell customers that the folks who endorsed it got the product free of charge and were paid for their promises.

It's nothing new for Congleton. Before teaming up with Walsh and Pascual for Green Coffee, Congleton owned a travel club company called Suncoast Incentives LLC. (He also owned its sister companies: United Vacation Network, Suncoast Vacations, Travel Services USA LLC, and Capital Financial Marketing.)

In 2012, the state pursued charges against all of these companies for deceiving customers. Among the allegations: that Suncoast would send postcards in the mail promising a "free cruise" just for showing up. Instead, the cruises had fees attached, and the airlines and resorts plastered on the postcard had no relationship with the company.